Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnlyHint, idempotentHint, and destructiveHint=false, so the safety profile is covered. The description adds real context beyond that: it never charges a fee or consumes a free trial call, and the default wallet is derived from the caller's client IP. It does not discuss rate limits or caching, but the cost/free-trial guarantee is meaningful behavioral disclosure.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.